Radiator fin

ABSTRACT

A radiator fin ( 10 ) has front ( 11 ) and rear ( 12 ) faces, and is defined by upper ( 15 ) and lower ( 16 ) edges and opposed side edges ( 17, 18 ). The fin ( 10 ) has first and second apertures ( 13, 14 ), each passing through the front ( 11 ) and rear ( 12 ) faces and adapted to receive and contact a conductive element ( 24, 25 ) for the transfer of heat to the fin ( 10 ). The centre of the first aperture ( 13 ) is offset relative to the centre of the second aperture ( 14 ), such that said first ( 13 ) and second aperture ( 14 ) centres are not vertically aligned when the fin ( 10 ) is installed. The fin ( 10 ) is adapted for mounting adjacent a plurality of like fins ( 10 ) to form a heat exchange coil ( 30 ) for use in a radiator ( 40 ).

This invention relates, in a first aspect thereof, to an improved design of radiator fin. In further aspects thereof, the invention relates to a heat exchange coil formed from a plurality of such fins, and to a radiator incorporating such coils.

Fin radiators (sometimes referred to as finned radiators) comprise a heat exchange coil provided with a plurality of fins extending from the heating element and in conductive contact therewith. The purpose of the fins is to increase the surface area of the heat exchange coil and thereby increase the efficiency of heat transfer from the heating element to the surrounding air.

Fin radiators for domestic use typically utilise a metal pipe adapted to deliver heater water from a water heating system through the heat exchange coil. The pipe is generally arranged so as to be horizontal as it passes through the heat exchange coil, with the fins arranged vertically so as to channel air upwards through the heat exchange coil and over and around the pipe. The heat exchange coil is generally housed within a decorative casing which can also serve to direct air flow. Fin radiators of this type have found use in perimeter heating applications, and in particular in low level heating installations on, or in place of, skirting boards or baseboards.

The applicant's own U.S. Pat. No. 5,406,937 describes a baseboard fin radiator having two horizontal pipes for the delivery of heated water, the pipes being arranged in vertical alignment with one another. The advantage of having two pipes is that either: both pipes may be used to deliver heated water to the radiator directly from the water heating system, thereby doubling the heat transfer efficiency; or one pipe may be designated a flow pipe to deliver heated water to the radiator directly from the water heating system, with the other pipe designated a return pipe to return water to the water heating system.

A previously unrecognised drawback of the system disclosed in U.S. Pat. No. 5,406,937 arises from the arrangement of the two pipes in vertical alignment. This results in air drawn up into the underside of the heat exchange coil flowing around the lower pipe, but then being diverted past the sides of the upper pipe. That is to say, the lower pipe effectively blocks the air stream from fully contacting the upper pipe. This occurs because the relatively small height of the radiator—necessitated by its installation as a baseboard heater—means that the separation between the upper and lower pipes is insufficient for the air to flow into the space between the pipes and then around the upper pipe, bearing in mind that the air flow is dictated only by natural convection. As a result of this restricted air flow around the upper pipe, the heat transfer efficiency of the unit is compromised.

The present invention seeks to provide an improved radiator fin, heat exchange coil, and fin radiator which overcome the above discussed drawbacks of the known prior art by enabling an enhanced air flow, thereby to optimise heat transfer efficiency.

According to a first aspect of the present invention there is provided a radiator fin having front and rear faces, and defined by upper and lower edges and opposed side edges, said fin having first and second apertures, each passing through the front and rear faces and adapted to receive and contact a conductive element for the transfer of heat to the fin, wherein the centre of the first aperture is offset relative to the centre of the second aperture, such that said first and second aperture centres are not vertically aligned when the fin is installed.

The construction of the fin with offset apertures serves to enhance heat transfer by ensuring that both conductive elements are fully presented to a stream of air drawn upward over the fin by natural convection, when the fin is installed. This is distinct from the undesirable arrangement of the prior art where the lower conductive element blocks the air stream from fully contacting the upper conductive element.

In order further to optimise the air flow, and hence the heat transfer efficiency, the fin preferably further comprises a plurality of flutes on at least one of the front and rear faces, said flutes being arranged so as to be vertically oriented when the fin is installed. The vertical fluting serves to increase the surface area of the fin, and also to direct air flow to the conductive elements. The provision of fluting on fins to increase surface area is known from the prior art, but such fluting tends to horizontal across the fin, which can be counter-productive for efficient air flow.

Whilst the fin may be of any shape or configuration, it is generally preferred that it be rectangular, with the upper and lower edges being substantially parallel to one another, and the opposed side edges being substantially parallel to one another and substantially perpendicular to the upper and lower edges. In rectangular embodiments of the fin, the flutes are preferably arranged substantially parallel to the opposed side edges.

The lower edge of the fin is preferably formed with a raised central section so as to present an oblique mounting surface adjacent the junction of the lower edge with each side edge, each said mounting surface being adapted to receive a mounting element of a radiator casing. This provides a simple but effective mechanism for removable attaching a radiator casing to the fin.

The conductive elements which the fin apertures are adapted to receive and contact may be of any configuration and may include for example electric heating elements. It is generally preferred however that each said conductive element for transfer of heat to the fin is a pipe connector adapted to enable delivery of heated water, for example from a domestic heating system.

The radiator fin according to the first aspect of the present invention may desirably be combined in an assembly of like fins to form a heat exchange coil suitable for use in a radiator.

Therefore, according to a second aspect of the present invention there is provided a heat exchange coil comprising a plurality of like radiator fins mounted adjacent one another, each said radiator fin having:

-   -   front and rear faces, being defined by upper and lower edges and         opposed side edges, and having first and second apertures, each         passing through the front and rear faces and adapted to receive         and contact a conductive element for the transfer of heat to the         fin, wherein the centre of the first aperture is offset relative         to the centre of the second aperture, such that said first and         second aperture centres are not vertically aligned when the fin         is installed,

and wherein the first aperture of each fin is aligned with the first aperture of each adjacent fin, and the second aperture of each fin is aligned with the second aperture of each adjacent fin, thereby to form first and second conduits extending through the heat exchange coil, each adapted to receive and contact a said conductive element for the transfer of heat to the fins.

The heat exchange coil according to the second aspect of the present invention may comprise a plurality of like radiator fins according to any embodiment of the first aspect of the present invention as hereinbefore described, mounted adjacent one another.

As noted above with reference to the first aspect of the invention, the conductive element for transfer of heat to the fins is preferably a pipe connector adapted to enable delivery of heated water. In such preferred embodiments, the heat exchange coil further comprises a first said pipe connector mounted in the first conduit, and a second said pipe connector mounted in the second conduit, each said pipe connector being adapted for connection to a water heating system thereby to deliver heated water to the heat exchange coil.

Preferably, one of said first and second pipe connectors is adapted for connection to a flow pipe to deliver heated water from the water heating system to the heat exchange coil, and the other of said first and second pipe connectors is adapted for connection to a return pipe to return water from the heat exchange coil to the water heating system. Alternatively, both first and second pipe connectors may be arranged for delivery of heated water to the heat exchange coil directly from the water heating system.

To further improve the heat transfer efficiency, at least one of said first and second pipe connectors may be provided with internal rifling. Alternatively, or additionally, at least one of said first and second pipe connectors may be provided with at least one internal swirler. These optional components serve to promote mixing, and thus temperature equalisation, within the water stream.

In embodiments of heat exchange coil which comprise a plurality of like radiator fins having oblique mounting surfaces as hereinbefore described, the oblique mounting surfaces of each fin are preferably aligned with the oblique mounting surfaces of each adjacent fin, thereby to form elongated oblique mounting surfaces extending along the underside of the heat exchange coil.

The heat exchange coil according to the second aspect of the present invention may desirably be combined with a radiator casing to form a fin radiator suitable for use as a baseboard heater.

Therefore, according to a third aspect of the present invention there is provided a radiator comprising:

-   -   a heat exchange coil formed from a plurality of like radiator         fins mounted adjacent one another, each said radiator fin         having:         -   front and rear faces, being defined by upper and lower edges             and opposed side edges, and having first and second             apertures, each passing through the front and rear faces and             adapted to receive and contact a conductive element for the             transfer of heat to the fin, wherein the centre of the first             aperture is offset relative to the centre of the second             aperture, such that said first and second aperture centres             are not vertically aligned when the fin is installed,         -   and wherein the first aperture of each fin is aligned with             the first aperture of each adjacent fin, and the second             aperture of each fin is aligned with the second aperture of             each adjacent fin, thereby to form first and second conduits             extending through the heat exchange coil, each adapted to             receive and contact a said conductive element for the             transfer of heat to the fins; and     -   a radiator casing adapted to be mounted on said heat exchange         coil.

The radiator according to the third aspect of the present invention may comprise a heat exchange coil formed from a plurality of like radiator fins according to any embodiment of the first aspect of the present invention as hereinbefore described, mounted adjacent one another.

Independently of the above, the radiator according to the third aspect of the present invention may comprise a heat exchange coil according to any embodiment of the second aspect of the present invention as hereinbefore described.

The radiator casing preferably comprises a back plate adapted to be secured to a wall, and further adapted to engage with the heat exchange coil, and a front panel adapted to engage with the back plate and with the heat exchange coil.

In preferred embodiments of radiator which comprise a heat exchange coil having oblique mounting surfaces as hereinbefore described, each of the back plate and the front panel preferably further comprises a mounting element adapted to engage with a respective oblique mounting surface.

Each of the front panel and the back plate preferably comprises an upper portion extending beyond the upper edge of the heat exchange coil, defined by the upper edges of the plurality of fins, thereby to define an air space above the heat exchange coil. The upper portion of the front panel preferably comprises a grille section located adjacent said air space, thereby to enable heated air to flow from said air space into a room in which the radiator is mounted.

The upper portion of the front panel may preferably be angled relative to the upper edge of the heat exchange coil, towards the back plate. Similarly, the upper portion of the back plate may preferably be angled relative to the upper edge of the heat exchange coil, towards the front panel. In such embodiments, the upper portion of the front panel is preferably adapted to engage with the upper portion of the back plate. This arrangement give rise to a chimney effect caused by the angled upper portion of the back plate directing warmed air in the air space out through the grille in the angled upper portion of the front panel. The angled upper portion of the back plate also serves to project the warmed air forwards and away from a wall on which the radiator is mounted. This helps to alleviate dust marks on walls and further to increase heating efficiency by projecting heat into the room rather than into the wall.

The radiator according to the third aspect of the present invention is preferably adapted to be installed on, or in place of, a skirting board or baseboard, and most preferably is adapted to be installed as a perimeter heating system.

In order that the present invention may be more clearly understood, a preferred embodiment thereof will now be described in detail, though only by way of example, with reference to the accompanying drawings, in which:

FIG. 1 shows a front view of a radiator fin according to a first aspect of the present invention;

FIG. 2 shows a perspective view of the radiator fin of FIG. 1;

FIG. 3 shows a top view of the radiator fin of FIGS. 1 and 2;

FIG. 4 shows a perspective view of a heat exchange coil according to a second aspect of the present invention; and

FIG. 5 shows a perspective view of a radiator according to a third aspect of the present invention.

Referring first to FIGS. 1 to 3, there is shown a preferred embodiment of radiator fin, generally indicated 10, according to a first aspect of the present invention. The fin has a front face 11 and a rear face 12 (shown in FIG. 3) with a first upper aperture 13 and a second lower aperture 14 passing therethrough. The fin 10 has a generally rectangular shape and is defined by opposed parallel upper and lower edges 15, 16 and opposed parallel first and second side edges 17, 18.

As can best be seen from FIG. 2, the front face 11 of the fin 10 is provided with fluting 19 taking the form of a number of vertical ridges, grooves or channels in or on the face 11 of the fin 10. These act to increase the surface area and channel air flow.

As can best be seen from FIG. 1, the centres of the upper and lower apertures 13, 14 are horizontally offset so that the apertures are not in vertical alignment. In use, when the fin is installed in a heat exchange coil 30 or radiator 40, as will be described in more detail below with reference to FIGS. 4 and 5, the apertures 13, 14 are each provided with a pipe connector 24, 25 adapted for the delivery of heated water from a heating system, as can be seen in FIG. 3. The offset arrangement of the apertures 13, 14, and hence the pipe connectors 24, 25 mounted therein, ensures a more efficient heat transfer by presenting both pipe connectors 24, 25 to an air stream rising from the lower edge 16 of the fin over the face 11 towards the upper edge 15, as a result of natural convection. The vertical fluting 19 further assists in directing the air stream to the pipe connectors 24, 25 in the apertures 13, 14.

As can best be seen in FIG. 1, the lower edge 16 of the fin 10 is formed with a raised central section 21 so as to present a first oblique mounting surface 22 adjacent the junction of the lower edge 16 with the first side edge 17, and a second oblique mounting surface 23 adjacent the junction of the lower edge 16 with the second side edge 18. In use, when the fin 10 is installed in a radiator 40, as will be described in more detail below with reference to FIG. 5, the oblique mounting surfaces 22, 23 engage with mounting elements of a radiator casing.

As can be seen from FIGS. 2 and 3, the fin 10 may be provided with protruding flanges 26 adjacent the side edges 17, 18 in order to provide constant spacing between adjacent like fins 10 when assembled together in a heat exchange coil 30. The flange 26 may either protrude over the front face 11 as shown in FIG. 2, or the rear face 12 as shown in FIG. 3.

The dimensions for the preferred embodiment of radiator fin 10 shown in FIGS. 1 to 3 are: a height of substantially 130 mm, and a width of substantially 70 mm. The horizontal separation between the centres of the apertures 13, 14 is substantially 28 mm, whilst the vertical separation is substantially 52 mm. The diameter of the apertures is substantially 22 mm. The centre of the upper aperture 13 is substantially 21 mm from the second side edge 18, and substantially 55 mm from the upper edge 15; whilst the centre of the lower aperture 14 is substantially 21 mm from the first side edge 17, and substantially 23 mm from the bottom of the lower edge 16 (that is, that part of the lower edge 16 which does not form the raised central section 21). The raised central section 21 has a vertical separation of substantially 6 mm over the bottom of the lower edge 16, and the oblique mounting surfaces 22, 23 each present an angle of substantially 45°, relative to the raised section 21.

Referring now to FIG. 4, a plurality of like fins 10 are mounted closely adjacent one another to form a preferred embodiment of heat exchange coil, generally indicated 30, according to the second aspect of the present invention. As can be seen, the flanges 26 of each fin provide a surface an adjacent fin to abut against, thus providing constant spacing throughout the array of fins 10 constituting the heat exchange coil 30. The fins 20 are aligned so that the apertures 13, 14 in each fin line up with the apertures 13, 14 in adjacent fins to form first and second conduits 31, 32 extending through the heat exchange coil 30. First and second pipe connectors 24, 25 are then mounted in said conduits 31, 32 such that there is a heat conductive connection between the pipe connectors 24, 25 and each fin 10.

The alignment of the fins 10 also enables the formation of extended oblique mounting surfaces (not visible in FIG. 4) by aligning the first oblique mounting surface 22 of each fin 10 with the first oblique mounting surface 22 on adjacent fins 10, and aligning the second oblique mounting surface 23 of each fin 10 with the second oblique mounting surface 23 on adjacent fins 10.

During use, heated water flows through the pipe connectors 24, 25 and heat is transferred to the fins 10. Warmed air rises up through the heat exchange coil 30 from the lower edges 16 towards the upper edges 15 of each fin 10, driven by natural convection. As it rises, the fluting 19 directs the air flow onto and around each pipe connector 24, 25 to maximise heat transfer efficiency.

Referring now to FIG. 5, there is shown a preferred embodiment of radiator, generally 40, according to a third aspect of the present invention. The radiator 40 incorporates the heat exchange coil 30 as described above with reference to FIG. 4, together with a radiator casing 41 comprising a front panel 42 and a back plate 43. The front panel 42 is provided with a mounting element 44 along its lower edge 45, which mounting element 44 is adapted to clip onto the extended first oblique mounting surface 22 of the heat exchange coil 30. Similarly, the back plate 43 is provided with a mounting element 46 along its lower edge 47, which mounting element 46 is adapted to clip onto the extended second oblique mounting surface 23 of the heat exchange coil 30.

The upper edge 48 of the front panel 42 and the upper edge 49 of the back plate 43 are shaped so as to have a complementary profile to one another such the upper edge 48 of the front panel 42 can clip over the upper edge 49 of the back plate 43 to retain the former in place. In use, the back plate 43 will be secured to a wall using conventional wall fixings (not shown).

As can also be seen from FIG. 5, the front panel 42 has an upper portion 51 which extends upwardly beyond the upper edges 15 of the fins 10 of the heat exchange coil 30. The upper portion 51 is also angled relative to the main part 52 of the front panel 42 and has a grille 53 therein to permit the flow of warmed air from the heat exchange coil 30 to the room in which the radiator 40 is located. The back plate 42 also has an upper portion 54 which extends upwardly beyond the upper edges 15 of the fins 10 of the heat exchange coil 30, and is also slightly angled relative to the main part 55 of the back plate 43. The construction of the radiator casing 41 in this way defines an air space 56 within the casing 41, above the heat exchange coil 30, in which warmed air can accumulate. The angled upper portion 54 of the back plate 43 causes a chimney effect which directs the warmed air out through the grille 53 and enhances the flow of air through the radiator 40 by natural convection. 

1. A radiator fin having front and rear faces, and defined by upper and lower edges and opposed side edges, said fin having first and second apertures, each passing through the front and rear faces and adapted to receive and contact a conductive element for the transfer of heat to the fin, wherein the centre of the first aperture is offset relative to the centre of the second aperture, such that said first and second aperture centres are not vertically aligned when the fin is installed.
 2. The radiator fin of claim 1, further comprising a plurality of flutes on at least one of the front and rear faces, said flutes being arranged so as to be vertically oriented when the fin is installed.
 3. The radiator fin of claim 2, wherein said fin is generally rectangular, and wherein the upper and lower edges are substantially parallel to one another, and the opposed side edges are substantially parallel to one another and substantially perpendicular to the upper and lower edges.
 4. The radiator fin of claim 3, wherein the flutes are arranged substantially parallel to the opposed side edges.
 5. The radiator fin of claim 1, wherein the lower edge is formed with a raised central section so as to present an oblique mounting surface adjacent the junction of the lower edge with each side edge, each said mounting surface being adapted to receive a mounting element of a radiator casing.
 6. The radiator fin of claim 1, wherein each said conductive element for transfer of heat to the fin is a pipe connector adapted for the delivery of heated water.
 7. A heat exchange coil comprising a plurality of like radiator fins mounted adjacent one another, each said radiator fin having: front and rear faces, being defined by upper and lower edges and opposed side edges, and having first and second apertures, each passing through the front and rear faces and adapted to receive and contact a conductive element for the transfer of heat to the fin, wherein the centre of the first aperture is offset relative to the centre of the second aperture, such that said first and second aperture centres are not vertically aligned when the fin is installed, and wherein the first aperture of each fin is aligned with the first aperture of each adjacent fin, and the second aperture of each fin is aligned with the second aperture of each adjacent fin, thereby to form first and second conduits extending through the heat exchange coil, each adapted to receive and contact a said conductive element for the transfer of heat to the fins.
 8. The heat exchange coil of claim 7, wherein each said conductive element for transfer of heat to the fins is a pipe connector adapted for the delivery heated water, and wherein the heat exchange coil further comprises a first said pipe connector mounted in the first conduit, and a second said pipe connector mounted in the second conduit, each said pipe connector being adapted for the delivery of heated water to the heat exchange coil.
 9. The heat exchange coil of claim 8, wherein one of said first and second pipe connectors is adapted for connection to a flow pipe for delivery of heated water from the water heating system to the heat exchange coil, and the other of said first and second pipe connectors is adapted for connection to a return pipe to return water from the heat exchange coil to the water heating system.
 10. The heat exchange coil of claim 8, wherein each of said first and second pipe connectors is adapted for connection to a flow pipe for delivery of heated water directly from the water heating system to the heat exchange coil.
 11. The heat exchange coil of claim 8, wherein at least one of said first and second pipe connectors is provided with internal rifling.
 12. The heat exchange coil of claim 8, wherein at least one of said first and second pipe connectors is provided with at least one internal swirler.
 13. The heat exchange coil of claim 7, comprising a plurality of like radiator fins each having a lower edge formed with a raised central section so as to present an oblique mounting surface adjacent the junction of the lower edge with each side edge, wherein the oblique mounting surfaces of each fin are aligned with the oblique mounting surfaces of each adjacent fin, thereby to form elongated oblique mounting surfaces extending along the underside of the heat exchange coil.
 14. A radiator comprising: a heat exchange coil formed from a plurality of like radiator fins mounted adjacent one another, each said radiator fin having: front and rear faces, being defined by upper and lower edges and opposed side edges, and having first and second apertures, each passing through the front and rear faces and adapted to receive and contact a conductive element for the transfer of heat to the fin, wherein the centre of the first aperture is offset relative to the centre of the second aperture, such that said first and second aperture centres are not vertically aligned when the fin is installed, and wherein the first aperture of each fin is aligned with the first aperture of each adjacent fin, and the second aperture of each fin is aligned with the second aperture of each adjacent fin, thereby to form first and second conduits extending through the heat exchange coil, each adapted to receive and contact a said conductive element for the transfer of heat to the fins; and a radiator casing adapted to be mounted on said heat exchange coil.
 15. The radiator of claim 14, wherein the radiator casing comprises a back plate adapted to be secured to wall, and further adapted to engage with the heat exchange coil, and a front panel adapted to engage with the back plate and with the heat exchange coil.
 16. The radiator of claim 15, wherein: the heat exchange coil comprises a plurality of like radiator fins each having a lower edge formed with a raised central section so as to present an oblique mounting surface adjacent the junction of the lower edge with each side edge; the oblique mounting surfaces of each fin are aligned with the oblique mounting surfaces of each adjacent fin, thereby to form elongated oblique mounting surfaces extending along the underside of the heat exchange coil; and, each of the back plate and the front panel further comprises a mounting element adapted to engage with a respective oblique mounting surface.
 17. The radiator of claim 15, wherein each of the front panel and the back plate comprises an upper portion extending beyond the upper edge of the heat exchange coil, defined by the upper edges of the plurality of fins, thereby to define an air space above the heat exchange coil, and wherein the upper portion of the front panel is adapted to engage with the upper portion of the back plate.
 18. The radiator of claim 17, wherein said upper portion of the front panel comprises a grille section located adjacent said air space, thereby to enable heated air to flow from said air space into a room in which the radiator is mounted.
 19. The radiator of claim 17, wherein the upper portion of the front panel is angled relative to the upper edge of the heat exchange coil.
 20. The radiator of claim 17, wherein the upper portion of the back plate is angled relative to the upper edge of the heat exchange coil. 